Computational Comparison of Debris Cloud Models

On-orbit breakup events give rise to concentrations of debris that, for some time after the event, have spatial densities considerably higher than the background  ux. Thus, a detailed knowledge of the extent to which the cloud will grow over a given time period and an accurate assessment of the risk of collision for a spacecraft passing through it are important considerations when determining the debris collision risk to orbiting spacecraft. This study examines and compares two sets of software models developed to address this problem and shows how such models can Ž nd use in real-life operational situations. Debris cloud modeling software developed at the University of Southampton is compared with The Aerospace Corporation’s models on a case study of the Clementine/Titan II second-stage fragmentation. The comparison shows that although good overall agreement between the modeling software is observed, signiŽ cant discrepancies still exist in themodelingof fragmentationevents, and true validation of the models with real data is still to be achieved.